+++ /dev/null
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-<HTML
-><HEAD
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->DNS</TITLE
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-CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
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-TITLE="eCos Reference Manual"
-HREF="ecos-ref.html"><LINK
-REL="UP"
-TITLE="DNS for eCos and RedBoot"
-HREF="net-ns-dns.html"><LINK
-REL="PREVIOUS"
-TITLE="DNS for eCos and RedBoot"
-HREF="net-ns-dns.html"><LINK
-REL="NEXT"
-TITLE="Ethernet Device Drivers"
-HREF="io-eth-drv-generic.html"></HEAD
-><BODY
-CLASS="CHAPTER"
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->eCos Reference Manual</TH
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-><DIV
-CLASS="CHAPTER"
-><H1
-><A
-NAME="NET-NS-DNS-API">Chapter 45. DNS</H1
-><DIV
-CLASS="SECT1"
-><H1
-CLASS="SECT1"
-><A
-NAME="NET-NS-DNS-API1">DNS API</H1
-><P
->The DNS client uses the normal BSD API for performing lookups:
-<TT
-CLASS="FUNCTION"
->gethostbyname()</TT
-> and
-<TT
-CLASS="FUNCTION"
->gethostbyaddr()</TT
->.</P
-><P
->There are a few restrictions:</P
-><P
-></P
-><UL
-><LI
-><P
->Only IPv4 is supported, ie IPv6 addresses cannot be looked
-up.</P
-></LI
-><LI
-><P
->If the DNS server returns multiple authoritive records
-for a host name, the hostent will only contain a record for the
-first entry.</P
-></LI
-><LI
-><P
->The code has been made thread safe. ie multiple threads
-may call
-<TT
-CLASS="FUNCTION"
->gethostbyname()</TT
->
- without causing problems to the hostent structure returned. What
-is not safe is one thread using both
-<TT
-CLASS="FUNCTION"
->gethostbyname()</TT
->
- and
-<TT
-CLASS="FUNCTION"
->gethostbyaddr()</TT
->.
-A call to one will destroy the results from the previous call
-to the other function.</P
-></LI
-></UL
-><P
->To initialise the DNS client the following function must be
-called:</P
-><TABLE
-BORDER="5"
-BGCOLOR="#E0E0F0"
-WIDTH="70%"
-><TR
-><TD
-><PRE
-CLASS="PROGRAMLISTING"
->#include <network.h>
-int cyg_dns_res_init(struct in_addr *dns_server)</PRE
-></TD
-></TR
-></TABLE
-><P
->where dns_server is the address of the DNS server
-the client should query. On Error this function returns -1, otherwise
-0 for success. If lookups are attemped before this function has
-been called, they will fail and return NULL.</P
-><P
->A default, hard coded, server may be specified in the CDL option
-<TT
-CLASS="LITERAL"
->CYGDAT_NS_DNS_DEFAULT_SERVER</TT
->. The use of this is
-controlled by <TT
-CLASS="LITERAL"
->CYGPKG_NS_DNS_DEFAULT</TT
->. If this is
-enabled, <TT
-CLASS="LITERAL"
->init_all_network_interfaces</TT
-> will
-initialize the resolver with the hard coded address. The DHCP client
-or user code my override this address by calling
-<TT
-CLASS="LITERAL"
->cyg_dns_res_init</TT
-> again. </P
-><P
->The DNS client understands the concepts of the target being
-in a domain. By default no domain will be used. Host name lookups
-should be for fully qualified names. The domain name can be set
-and retrieved using the functions:
-<DIV
-CLASS="FUNCSYNOPSIS"
-><A
-NAME="AEN14685"><P
-></P
-><P
-><CODE
-><CODE
-CLASS="FUNCDEF"
->int getdomainname</CODE
->(char *name, size_t len);</CODE
-></P
-><P
-><CODE
-><CODE
-CLASS="FUNCDEF"
->int setdomainname</CODE
->(const char *name, size_t len);</CODE
-></P
-><P
-></P
-></DIV
-></P
-><P
->Alternatively, a hard coded domain name can be set using CDL.
-The boolean <TT
-CLASS="LITERAL"
->CYGPKG_NS_DNS_DOMAINNAME</TT
-> enables this
-and the domain name is taken from
-<TT
-CLASS="LITERAL"
->CYGPKG_NS_DNS_DOMAINNAME_NAME</TT
->.</P
-><P
->Once set, the DNS client will first perform a lookup with the domain
-name appended. If this fails it will then perform a second lookup
-without the appended domain name. </P
-></DIV
-></DIV
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-CLASS="NAVFOOTER"
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